In recent years, the cost of heating oils has increased many-fold, leading to related increases in the costs of other heating fuels, such as coal, gas, wood, peat, etc., as well as substantial increases in the cost of electrical energy whereby a much greater interest in other sources of energy has been evinced.
The collection and use of solar heat energy has been in the foreground of such greater interest. However, there have been many drawbacks and difficulties encountered in the search for improved collection systems for solar heat energy. The initial cost of installation and the difficulty of installation of many solar heat energy collecting systems has prevented their more widespread acceptance. The heaviness in weight and the relative inflexibility of use of other systems has also contributed to a lack of more general approval. The use of glass, with its breakage considerations and lack of durability, has but added to the many problems of present day systems.